Switch contact mounting for rotary switches

ABSTRACT

A mounting for a contact blade on a carrier surface. The carrier surface has a boss which extends upwardly with openings in opposite side walls. Opposed tabs on the contact blade extend into the openings, securing the blade on the carrier. The method of assembly of the contact to the carrier in which the tabs initially extend at an angle from the plane of the contact, the contact and carrier are moved together with the tabs extending into the openings and the tabs are straightened.

United States Patent Lonnie J. Richardson Elgin, Ill.

May 27, 1969 J an 12, 1971 Oak hlectro/Netics Corporation a corporationof Delaware inventor Appl. No. Filed Patented Assignee SWITCH CONTACTMOUNTING FOR ROTARY SWITCHES 8 Claims, 13 Drawing Figs.

US Cl 200/11, 200/ l 66 Int. Cl H01h 19/58 Field of Search 200/1 1D,166lCTS [56] References Cited UNITED STATES PATENTS 3,209,110 9/1965Meyer 200/1 1(D)x 3,248,488 4/1966 Stephan 200/1 1(D) 3,288,949 11/1966Brown, Jr. 200/11(D) Primary ExaminerRobert K. Schaefer AssistantExaminer.l. R. Scott Attorney-Hofgren, Wegner, Allen, Stellman & McCordABSTRACT: A mounting for a contact blade on a carrier surface. Thecarrier surface has a boss which extends upwardly with openings inopposite side walls. Opposed tabs on the contact blade extend into theopenings, securing the blade on the carrier. The method of assembly ofthe contact to the carrier in which the tabs initially extend at anangle from the plane of the contact, the contact and carrier are movedtogether with the tabs extending into the openings and the tabs arestraightened.

PATENTEU JAN 1 2197! Y SHEET 1 OF 3 7; J ENVENTOR zaizzzzffilyfwATTORNEYS PATENTED mam SHEET 3 OF 3 EUR SWITCH CONTACT MOUNTING FORROTARY SWITCHES There are several types of electrical switches which usea blade contact, commonly in conjunction with a plurality of wipercontacts, as in a rotary or a slide switch. It is usual to mount thecontact blade on a carrierby legs which extend through the carrier ant.are deformed, securing it in place. See for example Allison US. Pat. No.2,196,433; Mastney US. Pat. No. 2,594,190; Williams U.S. Pat. No.2,960,581.

Deforming the legs is an assembly step which adds to the cost.Furthermore, where contact blades are provided on both sides of thecarrier, the positions of blade legs extending through the carrier limitthe possible contact locations and thus the versatility of the switch.

It is a principal object of this invention to provide a contact mountingwhich does not use legs extending through the carrier; and further toprovide an economical method for assembling the contacts to the carrier.

One feature of the invention is that the carrier has a supportingsurface, a retaining surface spaced therefrom and defining an openingtherebetween, and that the contact has a mounting tab which extends intothe opening. More specifically, a pair of openings are defined betweenthe retaining surface and the supporting surface and the contact has apair of mounting tabs, one received in each of the openings. Theopenings face in opposite directions and the tabs on the contact areopposed.

Another feature is that a boss extends outwardly from the supportingsurface and has opposed walls with an opening in each to defineoppositely facing openings. The contact has a hole therein whichreceives the boss and a pair of mounting tabs on the contact extend intothe openings.

A further feature of the invention is the method of assembling a contactto a carrier in which the carrier has a supporting surface with a spacedretaining surface defining a pair of oppositely facing openings and thecontact has a pair of opposed tabs extending at an acute angle from theplane of the contact. The method includes the steps of moving thecarrier and contact together with the tabs extending into the openingsand straightening the tabs to secure the contact to the carrier. Moreparticularly, the tabs are straightened either by movement against thecarrier supporting surface or by movement against a tool.

Further features and advantages of the invention will readily beapparent from the following specification and from the drawings, inwhich:

FIG. 1 is a plan view of a rotary switch section embodying theinvention;

FIG. 2 is a fragmentary section taken along line 2-2 of FIG.

FIG. 3 is an enlarged fragmentary section taken along line 3-3 of FIG.2;

FIG. 4 is a fragmentary plan view of the rotary switch contact carrierwithout the contact thereon;

FIG. 5 is a fragmentary section taken along line 5-5 of FIG. 4;

FIG. 6 is a plan view of the rotor blade blank;

FIG. 7 is an enlarged fragmentary section taken along the line 7-7 ofFIG. 6;

FIG. 8 is a fragmentary illustration of a position of the contact bladeand support during assembly;

FIG. 9 is a view similar to FIG. 8 with the parts assembled;

' FIG. 10 is a fragmentary plan view of a contact blade mounting in aslide switch, utilizing the invention;

FIG. 11 is a fragmentary elevation of the contact mounting of FIG. 10;

FIG. 12 is a partially assemblied view of the contact blade andsupporting surface for the slide switch of FIG. 10; and

FIG. 13 is a view similar to FIG. 12 showing the parts in assembledcondition.

A section of a rotary switch embodying the invention is shown in FIGS. 1through 3. A ringlike stator 20-has a plurality within the centralopening of stator 20 and having contact blades 25, 26 mounted on theupper and lower surfaces 27 28 thereof.

The switch stator 20 has diametrically opposed mounting ears 30 throughwhich strut screws 31 extend for mounting the switch section from asuitable support. Commonly such switch sections are mounted in elongatedstacks with a plurality of similar switch sections. A switch operatingshaft 32 extends through a central opening in the rotor carrier 23 toturn contacts 25 and 26 with respect to the stator 20. Where the switchsection is one of several in a rotary switch stack, shaft 32 operatesall the rotors.

Circular rotor carrier 23 has on each side thereof a plurality ofoutwardly extending bosses 35 spaced angularly around the periphery ofthe carrier. The contact blades 25, 26 have corresponding openings 36,FIG. 6, through which bosses 35 extend when the contacts are in positionon supporting surfaces 27, 28.

As best seen in FIGS. 3 and 5, each boss 35 has a pair of lateralsidewalls 37 in which there are lateral openings 38 above the adjacentsurface 27 of the rotor. The upper boundary of opening 38 is a retainingsurface 39 spaced from the carrier surface 27.

Where the rotor carrier 23 is molded of a plastic material, which is aconvenient method of manufacture, openings 38 are provided by includingin the mold a pin (not shown) which extends through the rotor bodydefining the passage 40 and having a width greater than the spacingbetween lateral walls 37.

Bosses 35 are preferably noncircular in cross section. In theillustrated rotary switch, they have a T-shaped cross section with thecrossbar at the carrier periphery and the leg extending radiallyinwardly therefrom. The lateral walls 37 are those of the leg of the T.1

The contact blade 25 illustrated in FIG. 6 has openings 36 for each ofthe bosses 35. The openings have a T-shaped configuration correspondingwith the cross section of the bosses. Tabs 42, FIG. 3, extend intoopenings 37, between retaining surface 38 and the carrier supportingsurface 27 holding the contact 25 in place. The tabs 42 associated witheach opening 36 are opposed to extend into the corresponding oppositelyfacing openings 37.

FIGS. 8 and 9 illustrate a method of assembling the contact blade to thecarrier. The blade blank, FIGS. 6 and 7, has the tabs 42 extendingdownwardly at an acute angle with respect to the plane of the contact,from fold lines 43 spaced apart a distance greater than the width of theleg portion of the T- shaped boss 35. The inner edges 44 of the tabs arespaced apart a distance slightly greater than the spacing of sidewalls36, but less than the width of opening 40. The contact 25 is placed onthe rotor carrier 23 with the openings 36 in align ment with bosses 35.This positionof the two rotor elements is illustrated in FIG. 8. Thecontact and carrier are then moved toward each other with tabs 42extending into openings 37. As contact 25 moves toward the supportingsurface 27 of the carrier, tabs 42 engage the corners 46 between thesupporting surface and opening 40. Continued movement of the'conta'ct,which may be caused by a tool 47, bends tabs 42 upwardly into thegeneral plane of contact 25, in which position they extend underretaining surface 38, FIG. 9, securing the contact blade to the carrier.

The rotor contact may be a full circle as illustrated in FIGS. 1 and 6,or may be one or more smaller segments, depending on the switchingaction which is desired. As the'contact has a pair of opposed tabs 42which extend into oppositely directed openings on each boss, a contactsegment may be mounted on a single boss and still have mechanicalstability.

The contact mounting of the present invention is notlimited to use in arotary switch. FIGS. 10 and 11 illustrate its incorporation in a slideswitch. The slide switch carrier "50, only a portion of which is shown,has mounting bosses "51 spaced along itslength. The slide switch statorwith its associated wiper contacts is not illustrated in FIGS. 10 and11. A suitable contact arrangement is shown, for example, in Mastney etal. U.S. Pat. No. 2,213,845.

The bosses have a base portion 52 with a rectangular cross section,there being openings 53 in the spaced sidewalls 54 of the base. As inthe rotary switch, carrier 50 may suitably be molded of plastic materialand the openings 53 formed by a mold member or pin, which extends intoan opening 57 in the carrier, from the opposite side. Contact blade 58is mounted on the carrier with bosses 51 extending through it. Opposedtabs 59 on the contact 58 extend into oppositely facing openings 53securing the contact in place. Intermediate mounting bosses 51 is acontact positioning boss 60 of circular cross section.

Contact blade 58 may be mounted on the carrier in much the same manneras is illustrated in FIGS. 8 and 9. In the event, however, that movementof the contact blade against the carrier surface does not provideadequate straightening of the contact tabs, an additional tool may beutilized as illustrated in FIGS. 12 and 13. Here, tool 47' forcescontact blade 58 against carrier 50 with tabs 59 extending into openings53. Tool 62 extends into opening 57 from the underside of carrier 50,urging the tabs 59 upwardly against the retaining surface 63 of boss 51.It will be understood that a tool of the character of element 62 may beutilized in a assembling either the rotary switch or the slide switchform of the invention.

l claim:

1. In a switch, contact mounting means comprising:

a carrier having a supporting surface;

boss means extending outwardly from said supporting surface and havingopposed sidewalls, each with an opening therein defining a retainingsurface spaced from said supporting surface;

a planar contact blade on said carrier; and

a pair of opposed mounting tabs integral with said contact,

each extending into one of said openings, engaging the associatedretaining surface to secure said contact on said carrier.

2. The contact mounting means of claiml in which said boss meansincludes a boss having opposed walls with an opening in each to defineoppositely facing openings, said contact having a hole therein receivingsaid boss, with a pair of opposed mounting tabs on said contact oneextending into each of said openings.

3. The contact mounting means of claim 2 in which a passage extendsthrough said carrier and into said boss, one dimension of the passagebeing greater than the corresponding dimension of the boss to define theopenings in said sidewalls, adjacent said supporting surfaces.

4. The contact mounting means of claim 2 in which said boss has a Tconfiguration, with said openings in the leg of the 5. The contactmounting means of claim 4 in which said carrier is a circular rotor, andthe leg of the T-shaped boss extends radially thereof.

6. The contact mounting means of claim 5 in which the cross bar of the Tis located farther from the center of the carrier than the leg.

7. The rotor mounting means of claim 2 having a plurality of bosses withopenings on the carrier with corresponding plural holes in and mountingtabs on said contact.

8. The contact mounting means of claim 3 in which said carrier hasback-to-back supporting surfaces with mounting bosses extendingoutwardly from each, the bosses on one supporting surface beingstaggered with respect to the bosses on the other surface.

1. In a switch, contact mounting means comprising: a carrier having asupporting surface; boss means extending outwardly from said supportingsurface and having opposed sidewalls, each with an opening thereindefining a retaining surface spaced from said supporting surface; aplanar contact blade on said carrier; and a pair of opposed mountingtabs integral with said contact, each extending into one of saidopenings, engaging the associated retaining surface to secure saidcontact on said carrier.
 2. The contact mounting means of claim 1 inwhich said boss means includes a boss having opposed walls with anopening in each to define oppositely facing openings, said contacthaving a hole therein receiving said boss, with a pair of opposedmounting tabs on said contact one extending into each of said openings.3. The contact mounting means of claim 2 in which a passage extendsthrough said carrier and into said boss, one dimension of the passagebeing greater than the corresponding dimension of the boss to define theopenings in said sidewalls, adjacent said supporting surfaces.
 4. Thecontact mounting means of claim 2 in which said boss has a Tconfiguration, with said openings in the leg of the T.
 5. The contactmounting means of claim 4 in which said carrier is a circular rotor, andthe leg of the T-shaped boss extends radially thereof.
 6. The contactmounting means of claim 5 in which the cross bar of the T is locatEdfarther from the center of the carrier than the leg.
 7. The rotormounting means of claim 2 having a plurality of bosses with openings onthe carrier with corresponding plural holes in and mounting tabs on saidcontact.
 8. The contact mounting means of claim 3 in which said carrierhas back-to-back supporting surfaces with mounting bosses extendingoutwardly from each, the bosses on one supporting surface beingstaggered with respect to the bosses on the other surface.